Extract from ABC News
The sixth assessment report from the Intergovernmental Panel on Climate Change (IPCC) does not make for particularly uplifting reading.
You will have seen headlines about "code red", "unequivocal human influence" and 1.5C of warming by 2030.
But if you are keen to delve further into the details, it does say quite a bit about Australia.
For starters, Australia's land areas have warmed by around 1.4C since 1910.
But it is not just about temperature — the shift in global systems caused by human influence is bringing "widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere", the IPCC says.
Disasters getting worse
It is difficult to find positives in the list of current and projected changes for Australia.
According to the IPCC report, there is high confidence that the intensity, frequency and duration of fire weather events will increase.
UNSW Canberra climate scientist Sarah Perkins-Kirkpatrick warns that many of these changes scale with global warming, so the more global warming we experience, the worse these extremes will be.
"Given
recent extreme events, for example the 2019-20 Black Summer and the
devastating 49.6C temperatures and following wildfires in Canada, have
occurred at only 1C warming, extreme events that occur of 5C, or even
3C, will be far more crippling," she said.
At the other extreme, don't let this year's bumper snow deceive you — average snow cover and depth have decreased and are projected to decrease further.
The IPCC reports medium confidence that heavy rainfall, river floods and sand and dust storms will increase.
In hot water
The assessment found marine heatwaves and ocean acidity have increased around Australia, a trend that is projected to continue, along with enhanced warming in the East Australian Current (of Finding Nemo fame).
Marine heatwaves and ocean acidity are bad news for coral reefs.
Meanwhile, in one of the quirks of climate change, the number of cyclones is expected to fall but the proportion of severe storms is expected to increase.
The impacts of more intense cyclones is not expected to be helped by rising sea levels.
The IPCC reports Australasia's relative sea level has risen at a higher rate than the global average in recent decades.
It is a trend predicted to continue into the next century, "contributing to increased coastal flooding and shoreline retreat along sandy coasts throughout Australia".
Cities are the hotspots
The urban heat island effect is a well-known reality of living in a city these days.
Basically,
cities generate and capture more heat because of their high-density
layouts and heat-absorbing materials like concrete and bitumen.
While the IPCC found the contribution to global warming from urbanisation was negligible, there was very high confidence that urbanisation had exacerbated the effects of global warming in cities.
James Goldie from Monash University said most of Australia's cities were going to see the impacts of climate change and urbanisation.
"The important thing is that in most of our cities, it is areas that are typically disadvantaged that are most exposed, because those are the areas that have less of that protective tree canopy cover."
Vegetating our cities could help reduce the heat impacts, but it did not absolve us of our obligations to stop emitting carbon, he said.
"Our cities are going to keep getting warmer until we get our greenhouse gas emissions down to zero."
Then there are different impacts depending on where in the country you are.
Eastern Australia
Cool-season rainfall is expected to decrease in the east, but, as with most of the globe, extreme rainfall is expected to become more common.
The IPCC projects agricultural and ecological droughts will increase at 2C global warming and greater, with a medium degree of confidence.
Southern Australia
For decades, the big story for southern Australia has been decreasing rainfall.
The IPCC report signals, with medium confidence, a projected reduction in mean rainfall, particularly in the cool season, leading to an increase in aridity and in meteorological, agricultural and ecological droughts.
But when it looks at the south-west, it is far more emphatic.
It states there has been a significant rainfall decrease from 1910 to 2019 in the south-west which it can attribute to human influence.
This reduction in rainfall is very likely to continue under all scenarios, according to the report, leading to more agricultural and ecological droughts.
Northern Australia
Aside from the aforementioned changes to cyclones, there has been an observed increase in mean and heavy rainfall and a decrease in droughts in the north.
But the report states "mean rainfall changes are uncertain" going forward.
Despite this uncertainty, increased heavy rainfall and river flooding is projected by mid-century.
Central Australia
The red centre is set to continue to get redder on the heat maps.
Central Australia has had greater increases in temperature than on the coasts and is projected to continue to warm more under all future scenarios.
Where to from here?
The report is at pains to point out that natural disasters like heatwaves, droughts and floods will be more widespread at 2C and beyond than at 1.5C of warming.
The implication being that even though some of these changes are baked in at this point, it is not too late to make a better future.
"We can avoid dangerous climate change by reducing emissions immediately and substantially; continued increases in heatwaves and many other extremes will occur if we don't," said Professor Julie Arblaster of Monash University.
"Every action that we can take now counts towards reducing the risks from climate change."
Note: The opening image is loosely based on the projected mean temperatures in 2081-2100 under the SSP3 emissions scenario, generated using the IPCC's Interactive Atlas, where you can experiment with different inputs to see how they might impact the future.
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